From f7b64fe806029e0a0454df132eec3c5ab576102c Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 29 Oct 2009 22:34:15 +0900 Subject: [PATCH] percpu: make access macros universal Now that per_cpu__ prefix is gone, there's no distinction between static and dynamic percpu variables. Make get_cpu_var() take dynamic percpu variables and ensure that all macros have parentheses around the parameter evaluation and evaluate the variable parameter only once such that any expression which evaluates to percpu address can be used safely. Signed-off-by: Tejun Heo --- include/linux/percpu.h | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/include/linux/percpu.h b/include/linux/percpu.h index e12410e55e0..f965f833a64 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -27,10 +27,13 @@ * we force a syntax error here if it isn't. */ #define get_cpu_var(var) (*({ \ - extern int simple_identifier_##var(void); \ preempt_disable(); \ &__get_cpu_var(var); })) -#define put_cpu_var(var) preempt_enable() + +#define put_cpu_var(var) do { \ + (void)(var); \ + preempt_enable(); \ +} while (0) #ifdef CONFIG_SMP @@ -182,17 +185,19 @@ static inline void *pcpu_lpage_remapped(void *kaddr) #ifndef percpu_read # define percpu_read(var) \ ({ \ - typeof(var) __tmp_var__; \ - __tmp_var__ = get_cpu_var(var); \ - put_cpu_var(var); \ - __tmp_var__; \ + typeof(var) *pr_ptr__ = &(var); \ + typeof(var) pr_ret__; \ + pr_ret__ = get_cpu_var(*pr_ptr__); \ + put_cpu_var(*pr_ptr__); \ + pr_ret__; \ }) #endif #define __percpu_generic_to_op(var, val, op) \ do { \ - get_cpu_var(var) op val; \ - put_cpu_var(var); \ + typeof(var) *pgto_ptr__ = &(var); \ + get_cpu_var(*pgto_ptr__) op val; \ + put_cpu_var(*pgto_ptr__); \ } while (0) #ifndef percpu_write @@ -304,7 +309,7 @@ do { \ #define _this_cpu_generic_to_op(pcp, val, op) \ do { \ preempt_disable(); \ - *__this_cpu_ptr(&pcp) op val; \ + *__this_cpu_ptr(&(pcp)) op val; \ preempt_enable(); \ } while (0) -- 2.39.5